Dry chemical fire extinguishing apparatus



H. R. WESSON DRY CHEMICAL FIRE EXTINGUISHING APPARATUS April 2, 1968 2 Sheets-Sheet 1 Filed April 20. 1966 107 i i 2 INVENTOR Z719 yaw/0! /%Jym ATTORNEYS April 2, 1968 H. R. W SSON 3,375,875

DRY CHEMICAL FIRE EXTINGUISHING APPARATUS Filed April 20, 1966 2 Sheets-Sheet 2 6'54 1 7 67 9 27 INVENTOR ATTORNEYS United States Patent 3,375,875 DRY CHEMICAL FIRE EXTINGUHSHING APPARATUS Harold R. Wesson, Fort Worth, Tex., assignor to Fire Boss, Inc., doing business as Fire Control Engineering Company, Fort Worth, Tex.

Filed Apr. 20, 1966, Ser. No. 543,934 8 Claims. (Cl. 1699) This invention relates to fire extinguisher apparatus and more particularly to fire extinguishing apparatus of the dry chemical type, wherein the fire extinguishing agent is a dry chemical powder material within a pressure vessel storage container and is agitated by mechanical movement of the container as the container moves to the discharge position and is aerated by pressurized gas to fluidize the powder material for discharge through a conduit upon a fire.

Fire extinguishing apparatus of the general type to which the present invention pertains is disclosed by US. Patents 2,923,360 and 3,040,816 which are assigned to the assignee of the present invention.

Such fire extinguishing apparatus has a normal or standby condition, and a use condition. To extinguish a fire, the apparatus must be transferred from the standby to the use condition.

The general object of this invention is to provide improved fire extinguishing apparatus of the type abovementioned, particularly as related to the transfer of the apparatus from the standby to the use condition.

More specifically, an object of the present invention is to provide improved fire extinguishing apparatus of the type above-mentioned, particularly as related to mechanical agitation of the dry chemical material during the transfer of the apparatus from the standby to the use condition.

Another object of the present invention is to provide improved fire extinguishing apparatus of the type abovementioned, particularly as related to movement of the pressure vessel container to the use position.

For a further understanding of the invention and further objects, features, and advantages thereof, reference may now be had to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic side elevational view of fire extinguishing apparatus in accordance with a preferred embodiment of the present invention;

FIG. 2 is an end elevational view of the apparatus of FIG. 1 as viewed from the right end thereof;

FIG. 3 is a diagrammatic view, partially in section, showing a dry chemical fire extinguishing system embodying features of the present invention;

FIG. 4 is an end elevational view of the apparatus of FIG. 1 as viewed from the left end thereof; and

FIG. 5 is a schematic perspectiveview showing details of the actuator latch assembly.

Referring now to the drawings, it may be seen that fire extinguishing apparatus embodying the present invention may include a pressure vessel container 11, a support frame 13, a pressurized gas source 15, a gas supply conduit assembly 17, a discharge conduit assembly 19, an actuator latch assembly 21, and a stop latch assembly 23.

The support frame 13 includes a conventional skid frame or sled having side member runners 27, 29 held in rigid spaced parallel relation by suitable cross-brace members 31. The support structure further includes first, second, and third bearing mount structures 33, 35, 37, each of which is made up of a pair of angle members 39 that converge upwardly from the side member runners and are bridged at their upper ends by a cross member 41. Each bearing mount structure 33, 35, 37 is disposed generally in a vertical plane that is normal to the side 3,375,875 Patented Apr. 2, 1368 member runners 27, 29. The first, second and third bearing mount structures are disposed respectively at the left end portion, the central portion, and the right end portion of the skid frame 25.

First, second, and third hearings or journals 43, 45, 47 are axially aligned and mounted respectively on each cross member 41 at the center portion thereof.

The pressure vessel container 11 is preferably spherical in shape, as shown, having a filler neck 49 disposed at the top of the sphere when the container is in the normal upright or standby position. The filler neck 49 is closed by a conventional removable cap 51. The container has a central axis indicated as 53 in FIG. 4. Fixed on opposite sides of the container are a pair of axially aligned trunnions 55, 57 which are journally mounted respectively on the first and second bearings 43, 45. The trunnions 55, 57 are disposed so as to provide a rotational axis (indicated as 59 in FIG. 4) which is parallel to and displaced laterally and vertically from the container central axis 53.

When the container is in its normal upright or standby position, as shown by the solid lines in FIG. 4, its central axis 53 is disposed laterally to the right of and vertically above the rotational axis 59 (as viewed in FIG. 4).. This means that the weight of the container 11 and its contents when in the normal upright position will tend to cause r0- tation of the container in the clockwise direction. Such clockwise rotation from the normal upright position is prevented by the actuator latch assembly 21 when it is in the latched condition.

The actuator latch assembly 21 includes a crank having a shaft portion 61 rotatably secured to the cross member 41 of the first bearing mount structure 33 and extending transversely thereof, with a latch arm 63 fixed to the end of the crank shaft 61 adjacent the container and an actuator arm 65 fixed to the crank shaft 61 at its other end. The free end portion of the actuator arm 65 is pivotally connected to an actuator rod 67 at one end thereof. The actuator rod 67 extends parallel to the first support structure cross member 41 and terminates in a handle 69. A main valve control arm 71 is pivotally connected to the actuator rod 67 intermediate its length for a purpose to be hereinafter described. The main valve control arm 71 is parallel to and of the same length as the actuator arm 65. Both the actuator arm 65 and the main valve control arm 71 carry their pivotal connection with the actuator rod in a respective slot 73. The actuator rod 67 is slidably secured to the cross member 41 of the first bearing mount structure 33 by means of boss sleeves 75. The actuator rod 67 is biased to the latch position by means of a compression spring 77. The latch arm 63 has a hook portion 79 which is engageable with a keeper 81 which is secured to the container 11.

Fixed to a cross brace member 31 of the skid frame 25 and extending upwardly therefrom is a stop structure 83 which includes stop bar 85. The stop bar 85 is disposed beneath the rotational axis 59 of the container and is engageable by a limit stop protrusion 87 when the container 11 is in the normal upright position and by a bumper stop protrusion 89 when the container is in the inverted position. The limit stop protrusion 87 and the bumper stop protrusion 89 are rigidly fixed and generally oppositely disposed on the exterior of the container 11.

The stop latch assembly 23 includes a lever 91 having a control arm portion 93 and a stop arm portion 95. The lever is supported for pivoting motion about a horizontal axis parallel to the container rotational axis 59 at the juncture of the control arm and stop arm portions by means of a pedestal support bracket 97 which is fixed to a cross brace member 31 of the skid frame 25 and extends upwardly therefrom. The lever stop arm portion is biased by a compression spring 99 to the latched position.

The free end of the stop arm portion 95 abuts a stop face 1111 of the bumper stop protrusion 89 when the container 11 is in the inverted position.

A circular roll bar 103 is fixed to the exterior of the container 11 at the left side thereof and is disposed to have its central axis coincident with the container rotational axis 59. The roll bar 103 is utilized in the manual return of the container to the upright position.

A pressurized gas source is provided in the form of a conventional high pressure gas storage cylinder 135 filled with nitrogen or other suitable, preferably inert, gas. The gas storage cylinder 105 is cradled in a conventional manner on the skid frame by suitable bracket means 107 and is retained in place by suitable conventional clamp means 109. The gas storage cylinder 1115 is fitted with the usual outlet valve 111.

The gas supply conduit means 17 is connected at one end to the gas storage cylinder outlet valve 111 (see FIG. 3) and communicates via the left trunnion 55 to the container interior and terminates adjacent the top thereof. The gas supply conduit means 17 includes a high pressure section 113 connected between the cylinder outlet valve 111 and a pressure reducing valve 115, a working pressure section 117 connected between the pressure reducing valve 115 and a check valve 119, and a container interior section 121 connected to the check valve 119 and extending via the left to trunnion 55 to the container interior. A high pressure control valve 123 is interposed in the high pressure section 113 adjacent the outlet valve 111. A high pressure gauge 125 is interposed in the high pressure section 113 adjacent the pressure reducing valve 115. A main valve 127 is interposed in the working pressure section 117 between the pressure reducing valve 115 and the check valve 119. The main valve 127 is controlled by the actuator rod 67 of the actuator latch assembly 21 by means of the main valve control arm 71. A working pressure gauge 129 is interposed in the working pressure section 117 adjacent the check valve 119.

The discharge conduit assembly 19 includes a discharge hose 131 having a discharge nozzle 133 at its outer end and a discharge control valve 135 adjacent the discharge nozzle. The discharge hose 131 is preferably stored on a hose reel 137 having a support shaft 139 journally mounted on the second and third bearings 45, 47 hereinbefore mentioned. The inner end of the discharge hose 131 connects to one end of a rotary coupling 14-1 which serves a portion of the hose reel support shaft 139. A ring gear 143 is fixed to the right end portion of the hose reel 137 and is concentric with the hose reel shaft 139. A hose reel crank shaft 145 is rotatably supported by a bearing sleeve 147 which is fixed to the third bearing mount structure 47. The hose reel crank shaft 145 carries a drive pinion 149 which engages the ring gear 143. A conventional friction lock device 151 clamps the hose reel crank shaft 145 to prevent rotation of the hose reel 137 When that is desired. The rotary coupling 141 on the side opposite the discharge hose 131 communicates via the right trunnion 57 with a discharge manifold 153 disposed adjacent the right trunnion within the pressure vessel container 11. A pair of discharge conduit input sections 155, 157 communicate with the manifold 153 at one end and terminate at the other end adjacent the container top.

The gas supply conduit means and attendant valves and gauges and the discharge conduit assembly may all be of any suitable conventional form. For further details of these and other conventional components and arrangements, reference is made to US. Patents 2,923,360 and 3,040,816 hereinbefore mentioned.

Although the operation of the fire extinguishing apparatus shown in the drawings will be understood from the foregoing description by persons skilled in the art, a typical mode of peration will now be described.

The pressure vessel container 11, while in the upright position as shown by solid lines in FIG. 4, is filled with dry chemical powder material by removing the cap 51 and pouring through filler neck 49. Then the cap 51 is replaced. The discharge control valve 135 is in the closed position, as is the main valve 127, the high-pressure control valve 123 and the outlet valve 111. A fully charged gas storage cylinder is of course connected to the high-pressure section 113 of the gas supply conduit means 17. The hose reel friction lock device 151 is in the locked position, with the discharge hose 131 wound up on the hose reel 137. The outlet valve and the high-pressure control valve are opened. The apparatus is thus placed in the standby condition.

When a fire is to be attacked, the discharge hose 131 is unreeled by a hose-man who takes a position near the fire, manning the discharge nozzle 133 and the discharge control valve 135. An operator adjacent the fire extinguishing apparatus actuator latch assembly 21 pulls the actuator rod handle 69 outwardly, thus simultaneously unlatching the pressure vessel container by disengaging the hook portion 79 of the latch arm 63 from the keeper 81 and opening the main valve 127. When the pressure vessel container is unlatched, it will immediately begin moving, due to the force of gravity, in a clockwise direction (as seen in FIG. 4) toward the inverted position (which is shown by the dotted line in FIG. 4). Opening of the main valve 127 allows gas to flow from the storage cylinder 105 via the high-pressure conduit section 113, the pressure reducing valve 115, the working pressure conduit section 117, the main valve 127, the check valve 119, and the container interior conduit section 121 to the container interior adjacent the top thereof, where it is discharged at high velocity from the container interior conduit section terminal opening. Thus, as the pressure vessel container rotates to the inverted position, gas under pressure is being introduced at high velocity into the container interior, so that the dry chemical powder material is mechanically agitated by the rolling action of the sphere and aerated by the swirling gas stream to thoroughly fiuidize the powder material and render it amenable to flow freely into the input sections 155, 157 of the discharge conduit assembly and from the container. By the time the pressure vessel container approaches the inverted position, it has attained a substantial rotational velocity, and consequently when the bumper stop protrusion 89 strikes the stop bar 85, there is a significant shock effect, which enhances the mechanical agitation of the dry chemical powder material. As the pressure vessel container approaches the inverted position, the bumper stop protrusion 89 contacts the lever stop arm portion 95 of the stop latch assembly 23, pushing it downwardly to com;- press the compression spring 99. The bumper stop protrusion clears the end of the lever stop arm portion 95 an instant before the protrusion 89 contacts the stop bar 85, at which instant the compression spring 99 forces the lever stop arm portion upwardly behind the stop face 101 of the bumper stop protrusion 89. Thus, the pressure vessel container 11 is latched in the inverted position and is now in the use condition.

After the pressure vessel container 11 has been latched in the inverted position, and the working pressure gauge 129 indicates a steady pressure condition, which is ordinarily attained at about the time the inverted position latching is completed, the hose-man is notified and proceeds to operate the discharge control valve so that the fluidized dry chemical powder material flows via the discharge conduit assembly input sections 155, 157, the discharge manifold 153, the discharge hose 131, and through the nozzle 133 upon the fire.

When the fire has been extinguished, the discharge control valve 135 is closed, the discharge hose 131 is wound back onto the drum by rotation of the hose reel crank shaft 145, and the friction lock device 151 is locked. Then the stop latch assembly lever control arm portion 93 is raised upwardly so that the bumper stop protrusion is clear of the lever stop arm portion, and the pressure vessel container is rotated counterclockwise manually by means of the roll bar 103 until the limit stop protrusion 87 contacts the stop bar 105. As the pressure vessel container 11 approaches the normal upright position, keeper 81 of the actuator latch assembly 21 cams the crank latch arm to rotate same in the counterclockwise direction, compressing the actuator latch assembly compression spring 77. When the pressure vessel container 11 arrives at the upright position, the keeper 81 moves into the hook portion 79, the crank latch arm being returned in the clockwise direction by the force of the compression spring 77 to the latched position. Movement of the crank latch arm 63 to the latched position automatically also moves main valve control arm 71 to the closed position. The gas still under pressure within the container 11 is now employed to blow out the discharge line by momentarily opening the discharge control valve 135, thereby clearing the lines and relieving the pressure in the container. The check valve 119 prevents reverse flow through the gas supply conduit working pressure section 117 and thus prevents contamination of the valves, gauges, etc., with powder material. The highpressure control valve 123 and the outlet valve 111 are then closed and the apparatus is recharged and placed in standby condition in preparation for a subsequent use.

An important feature of the present invention resides in the provision of a pressure vessel container rotational axis 59 that is parallel to the pressure vessel container central axis 53 and displaced laterally therefrom. This axis displacement permits the pressure vessel container to move in a free fall condition from the normal upright position to the inverted position when the actuator latch assembly 21 is unlatched. This lateral axis displacement provides a foolproof pressure vessel container inversion action, since the force of gravity is always dependable, and since there is no rotational drive apparatus to malfunction. Also, the rotational drive apparatus that would otherwise be required, is eliminated, with consequent simplification of structure and resulting economies.

In the preferred embodiment of the invention, the pressure vessel container rotational axis 53 is displaced vertically as well as laterally from its central axis 59. This compound axis displacement results in reduction of the degree of eccentricity of the pressure vessel container rotation for a given free fall elfect. This means that the apparatus can be made more compact than otherwise. Also, the apparatus must utilize surface aligning bearings, and the compound axis displacement distributes any misalignment more evenly between the opposite vessol trunnions, for a given free fall effect. It has been found in practice that, for a pressure vessel container of about twenty-eight inches in diameter, a displacement of the pressure vessel container rotational axis 59 about one inch below and about one inch laterally of the vessel central axis 53 (as indicated in FIG. 4) is satisfactory.

In accordance with another feature of the present invention, there is further provided bumper means 89 on the container 11 and stop means 85 on the support frame 13, with the stop means being engaged by the bumper means to stop forward rotational movement of the container when it reaches the inverted position, with latch means 23 coacting with the support frame 13 and the container (particularly bumper stop protrusion 89) to prevent reverse rotational movement of the container upon reaching the inverted position.

The foregoing disclosure and the showings made in the drawings are merely illustrative of the principles of this invention and are not to be interpreted in a limiting sense.

While I have shown my invention in only one form it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

I claim:

1. A fire extinguishing apparatus of the type designed to utilize dry chemical powder material as the extinguishing agent, said apparatus comprising:

(a) a normally upright, sealed, pressure vessel container for storing the dry chemical powder material;

( b) gas supply conduit means adapted for connection to a source of pressurized gas and communicating with the interior of said container, with said gas supply conduit means terminating in said container adjacent the top thereof;

(c) normally closed gas valve means interposed in said gas supply conduit means and operable to admit gas under pressure from said source to said container;

(d) discharge conduit means communicating with the interior of said container and terminating in said container adjacent the top thereof;

(e) normally closed discharge valve means interposed in said discharge conduit means;

(f) said pressure vessel container having a central axis and a wall that is circular in transverse section and is disposed symmetrically about said central axis;

(g) a pair of trunnions fixed to said container and providing a rotational axis therefor, with said rotational axis being parallel to said central axis and displaced laterally therefrom;

(h) asupport frame;

(i) means journally mounting said trunnions on said support frame;

(j) latch means normally in the latched condition to hold said container against movement away from the upright position;

(k) and means for actuating said latch means to the unlatched condition to allow free fall rotational movement of said container to an inverted position.

2. The apparatus as defined by claim 1, wherein said container has a spherical shape.

3. The apparatus as defined by claim 1, wherein said rotational axis is also displaced vertically from said central axis.

4. The apparatus as defined by claim 3, wherein said container has a spherical shape.

5. The apparatus as defined by claim 1, wherein there is further provided bumper means on said container and stop means on said support frame, with said stop means engaged by said bumper to stop forward rotational movement of said container when it reaches the inverted position, and latch means coacting with said support frame and said container to prevent reverse rotational movement of said container when it reaches the inverted position.

6. The apparatus as defined by claim 5, wherein said container has a spherical shape.

7. The apparatus as defined by claim 5, wherein said rotational axis is also displaced vertically from said central axis.

8. The apparatus as defined by claim 7, wherein said container has a spherical shape.

References Cited UNITED STATES PATENTS 2,923,360 2/1960 Porter 169-31 3,040,816 6/1962 Slough 169--9 EVERETT W, KIRBY, Primary Examiner. 

1. A FIRE EXTINGUISHING APPARATUS OF THE TYPE DESIGNED TO UTILIZE DRY CHEMICAL POWDER MATERIAL AS THE EXTINGUISHING AGENT, SAID APPARATUS COMPRISING: (A) A NORMALLY UPRIGHT, SEALED, PRESSURE VESSEL CONTAINER FOR STORING THE DRY CHEMICAL POWDER MATERIAL; (B) GAS SUPPLY CONDUIT MEANS ADAPTED FOR CONNECTION TO A SOURCE OF PRESSURIZED GAS AND COMMUNICATING WITH THE INTERIOR OF SAID CONTAINER, WITH SAID GAS SUPPLY CONDUIT MEANS TERMINATING IN SAID CONTAINER ADJACENT THE TOP THEREOF; (C) NORMALLY CLOSED GAS VALVE MEANS INTERPOSED IN SAID GAS SUPPLY CONDUIT MEANS AND OPERABLE TO ADMIT GAS UNDER PRESSURE FROM SAID SOURCE TO SAID CONTAINER; (D) DISCHARGE CONDUIT MEANS COMMUNICATING WITH THE INTERIOR OF SAID CONTAINER AND TERMINATING IN SAID CONTAINER ADJACENT THE TOP THEREOF; (E) NORMALLY CLOSED DISCHARGE VALVE MEANS INTERPOSED IN SAID DISCHARGE CONDUIT MEANS; (F) SAID PRESSURE VESSEL CONTAINER HAVING A CENTRAL AXIS AND A WALL THAT IS CIRCULAR IN TRANSVERSE SECTION AND IS DISPOSED SYMMETRICALLY ABOUT SAID CENTRAL AXIS; (G) A PAIR OF TRUNNIONS FIXED TO SAID CONTAINER AND PROVIDING A ROTATIONAL AXIS THEREFOR, WITH SAID ROTATIONAL AXIS BEING PARALLEL TO SAID CENTRAL AXIS AND DISPLACED LATERALLY THEREFROM; (H) A SUPPORT FRAME; (I) MEANS JOURNALLY MOUNTING SAID TRUNNIONS ON SAID SUPPORT FRAME; (J) LATCH MEANS NORMALLY IN THE LATCHED CONDITION TO HOLD SAID CONTAINER AGAINST MOVEMENT AWAY FROM THE UPRIGHT POSITION; (K) AND MEANS FOR ACTUATING SAID LATCH MEANS TO THE UNLATCHED CONDITION TO ALLOW FREE FALL ROTATIONAL MOVEMENT OF SAID CONTAINER TO AN INVERTED POSITION. 